GB1436499A - Spectrally supersentized silver halide photographic emulsion - Google Patents

Abstract

1436499 Supersensitized silver halide emulsions FUJI PHOTO FILM CO Ltd 6 Aug 1974 [6 Aug 1973] 34681/74 Heading G2C A silver halide photographic emulsion contains a supersensitizing amount of at least one benzimidooxacarbocyanine dye of the general Formula wherein Z represents a substituent; R<SP>0</SP>, R<SP>1</SP> and R<SP>2</SP> each represents an aliphatic group, with at least one of R<SP>1</SP> and R<SP>2</SP> representing a carboxyalkyl or sulphoalkyl group; Y represents a halogen atom; X- is an anion; n is zero when the dye forms an intra-molecular salt, or 1; q is 0 to 4; and at least one merocyanine dye of the general Formula wherein Z<SP>1</SP> represents the non-metal atoms which complete an optionally-substituted 5-or-6- membered heterocyclic ring which may be fused; Q represents the atoms which complete an optionally substituted rhodamine, 2-thio- 2,4-imidazolinedione, 2-pyrazoline -5-one or a 2-thio -2,4-oxazolidinedione nucleus; R<SP>3</SP> represents an aliphatic group; R<SP>4</SP> represents a hydrogen atom, an alkyl group, an alkoxy group or a phenyl or carboxy phenyl group ; and m and p are each 0 or 1. Radicals specified are chlorine for Y: halogen, alkyl, cyano, aryl, trifluoromethyl, hydroxy, alkyl or alkyl sulphone for Z; Cl<SP>-</SP>Br<SP>-</SP>, CNS<SP>-</SP>, sulphate, ClO 4 <SP>-</SP>, p-toluene sulphonate or methylsulphate. Z<SP>1</SP> may complete an optionally fused thiazole, thiazoline, oxazole, selenazole, indolenine, imidazole, tetrazole or pyridine ring. Substituents in Z<SP>1</SP> may be alkyl, aryl, halogen, alkoxy, carboxy, aralkyl, -CF 3 , -OH, alkoxy carbonyl or cyano. The emulsion may also contain a red light-sensitive sensitizing dye.